package targetToOffer.eigthDay;

import com.sun.javafx.font.freetype.HBGlyphLayout;

/**
 * @author Godc
 * @description
 */
public class MergeTwoLists {
}
class MergeTwoListsSolution {
    public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
        if(l1==null) return l2;
        if(l2==null) return l1;
        ListNode head = new ListNode(0),temp = head;
        while(l1!=null&&l2!=null){
            if(l1.val<l2.val){
                temp.next = l1;
                l1 = l1.next;
            }else{
                temp.next = l2;
                l2 = l2.next;
            }
            temp = temp.next;
        }
        temp.next = (l1==null)?l2:l1;
        return head.next;
    }

    /**
     * 递归写法
     * @param l1
     * @param l2
     * @return
     */
    public ListNode mergeTwoLists1(ListNode l1, ListNode l2){
        if(l1 == null) return l2;
        if(l2 == null) return l1;
        if(l1.val <= l2.val) {
            l1.next = mergeTwoLists1(l1.next, l2);
            return l1;
        } else {
            l2.next = mergeTwoLists1(l1, l2.next);
            return l2;
        }

    }
}
class ListNode {
      int val;
      ListNode next;
      ListNode(int x) { val = x; }
}